there is lots of factors including .weather ,how hard u fly the bird ,how health the bird is in ect ect .normal food giving the hawks in flying/hunting condition is d.o.c's and rabbits ,some use supplients.and i dont mind giving a bit of partrage,quail ect if the bird is having a day of.in the moult ur giving mainly lots of high quality foods like the latter i mentioned.
a long wing u can give them and better of giving them high quality foods as these are like a farrari compared to a harris that is more like a mini ,you can crop up a faclon and if you watch it you can almost see it going down